JP2000209050A - Electronic volume device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic volume device which can reduce its circuit scale and also can improve its characteristic. SOLUTION: This device includes an electronic volume 1 and a common volume control circuit 2 which receives the input of different set data 31, 32,...3n to control the volume 1 and then attains the different volume functions by those set data. Thus, it is possible to reduce the circuit scale and to improve the performance of an electronic volume device by controlling the volume 1 via the circuit 2 which receives the different set data.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic volume control device, and more particularly to a control circuit for an electronic volume control.

[0002]

2. Description of the Related Art A plurality (n) of electronic volumes are built in,
In a circuit configured to cascade them, conventionally, as shown in FIG. 6, n volume control circuits 21 to 2n are individually provided for n volumes 11 to 1n.

The volume control circuits 21 to 2n are set by a control MCU 4C or the like, and are controlled by an MCU-I / F 4
Setting data 31 to 31
3n.

In the above-mentioned circuit configuration, a plurality of electronic volume and volume control circuits are required, so that the larger the number of cascaded volumes, the larger the circuit scale. In addition, since a plurality of electronic volumes are connected in cascade, noise and distortion generated in each electronic volume stage are superimposed, so that the characteristics of the output signal deteriorate.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to reduce the circuit scale and improve the characteristics by changing the configuration of a control circuit for an electronic volume.

[0006]

An electronic volume device according to a first aspect of the present invention includes an electronic volume and a common volume control circuit for receiving different setting data and controlling the electronic volume, respectively. Thus, different volume functions are realized.

According to a second aspect of the present invention, in the volume control circuit according to the first aspect of the present invention, the volume control circuit further includes an adding means for adding different setting data, and a decoder for processing an addition result by the adding means. By setting the output of the volume control circuit according to the output of the decoder, different volume functions are realized.

[0008] In the electronic volume device according to the third aspect of the invention, the electronic volume, setting data for realizing a function as a master volume, and setting data for realizing a function as a trimmer whose adjustment range is relatively narrower than the master volume. , And a common volume control circuit for controlling the electronic volume, and a function as a master volume and a function as a trimmer are realized by respective setting data.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 The configuration is as shown in FIG. In the figure, 1 is an electronic volume, 2 is a volume control circuit, 31 is volume (1) setting data, 3
2 is volume (2) setting data, and 3n is volume (n) setting data. Reference numeral 4 denotes an MCU interface circuit (hereinafter, referred to as MCU-I / F), and reference numeral 4C denotes a control MCU.

Embodiment 1 of the present invention shown in FIG.
Conventionally, each of the volume setting data 31 to 3n is decoded, the volume control circuit 2 for controlling the gain of each volume is reduced to one, and the plurality of cascaded electronic volumes 1 are reduced to one.

For the sake of simplicity, consider a case in which two-stage cascaded electronic volumes controlled by three bits and capable of setting eight stages from 0 to -7 dB as shown in FIG. Specifically, the volume control circuit 2 has a configuration as shown in FIG. 3, and includes an adder 5 for adding the volume (1) setting data 31 and the volume (2) setting data 32,
The decoder 6 is set as shown in FIG.

Now, for example, if the volume (1) is -2d
B (setting data “010”), volume (2) is −3
It is assumed that dB (setting data “011”) is set. The volume (1) setting data 31 (“010”) and the volume (2) setting data 32 (“011”) are added by the adder 4 to become data (“101”). This data is used by the decoder 6 to reduce the gain of the volume 1 by -5.
It is set to be dB.

Therefore, the gain from input to output is-
5 dB, and only one volume is used as a circuit configuration. However, as volume control, it is possible to set data of the volume (1) and the volume (2) in an independent manner.

As described above, in the first embodiment of the present invention, the electronic volume 1 is controlled by the common volume control circuit 2 to which different setting data is input, and the volume control circuit 2 is integrated. Since the number of electronic volumes 1 is one, the circuit scale can be reduced and the characteristics can be improved.

In the first embodiment according to the present invention,
In the above-described configuration, an adding means including an adder 5 for adding different setting data is provided, and a decoder 6 for processing an addition result by the adding means is provided, and an output of the volume control circuit 2 is set according to an output of the decoder 6. By doing so, different volume functions are realized, so that more stages of volume control can be performed with relatively small volume setting data, and the circuit size can be reduced and the characteristics can be more effectively improved. it can.

As a prior art disclosed in the publication, there is Japanese Utility Model Publication No. Sho 62-51882, which discloses one volume setting data (for example, volume (1) shown in FIG. 3) Only the data corresponding to the setting data 31) is described, and both are clearly different in the content of the invention.

The prior art setting devices (1) to (3) 11
In the embodiment of the present invention, a to c correspond to the volume setting data (eg, “010”, “100”, etc.) shown in FIG. 2, and the volume setting value is determined based on this data.

Regarding the increase or decrease of the volume, the counter 13 is operated by a pulse signal output periodically from the pulse generator 17 and controlled by the output. This is similar to the case where the volume setting data shown in FIG. 2 is counted up or down one by one in the embodiment according to the present invention.

The setting device (4) 15c is data for determining the maximum allowable value of the volume. In the embodiment according to the present invention, it corresponds to "000" in FIG. 3 and controls the volume so as not to exceed "000". Therefore, the setting device (3) 11c and the setting device (4) 15c can be regarded as one volume setting data, which is different from that of the present invention.

Embodiment 2 Embodiment 2 as an application example of the present invention will be described below. For example, a Dolby Pro Logic system has a configuration as shown in FIG.
The signal decoded to 4ch is output through a trimmer 1T (a type of volume) and a volume 1V.

The trimmer 1T uses each channel (L, R, C, and C) to optimally set the sound field effect for the listener.
The setting range for adjusting the balance of S) is relatively narrow (example:
+10 dB to -10 dB) volume. The volume 1V is a master volume for adjusting the entire signal level, and has a setting range of about 0 to 76 dB.

Here, the trimmer 1T and the volume 1V shown in FIG. 5 are equivalently described as showing their respective functions, and are shown as being cascade-connected to each other. The functions of the trimmer 1T and the volume 1V are different from those of the electronic volume 1 shown in FIG. Common volume control circuit to which setting data is input (corresponding to control circuit 2 in the first embodiment shown in FIG. 1)
Is achieved by controlling the

In the second embodiment of the present invention, the electronic volume 1 is controlled by a common control circuit to which setting data for realizing the function as the master volume 1V and setting data for realizing the function as the trimmer 1T are input. By controlling, the functions of the trimmer 1T and the volume 1V are realized by one volume 1, so that the circuit scale can be reduced and the characteristics such as noise can be improved.

[0024]

According to the first aspect of the invention, the electronic volume is controlled by the common volume control circuit to which different setting data is input, so that the circuit scale can be reduced and the characteristics can be improved. Can be.

According to the second invention, in the first invention, an addition means for adding different setting data is provided, and a decoder for processing an addition result by the addition means is provided, and a volume control circuit is provided in accordance with an output of the decoder. By setting different outputs, different volume functions are realized, so that more stages of volume control can be performed with relatively small volume setting data, and the circuit size is reduced and the characteristics are further improved. Can be realized.

According to the third invention, the electronic volume is
The function of the master volume and the function of the trimmer are controlled by a common volume control circuit to which different setting data is input, so that the circuit scale can be reduced and the characteristics such as noise can be improved.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a first embodiment according to the present invention.

FIG. 2 is an explanatory diagram showing a setting operation according to the first embodiment of the present invention.

FIG. 3 is a block diagram showing a volume control circuit according to the first embodiment of the present invention.

FIG. 4 is an explanatory diagram illustrating a setting operation in the volume control circuit according to the first embodiment of the present invention;

FIG. 5 is a block diagram showing a configuration of a second embodiment according to the present invention.

FIG. 6 is a block diagram showing a configuration of a conventional example.

[Explanation of symbols]

1 volume, 2 volume control circuit, 31 volume (1) setting data, 32 volume (2) setting data, 3n volume (n) setting data, 4 MC
U-I / F, 4C control MCU.

Claims (3)

[Claims] An electronic volume and a common volume control circuit that receives different setting data and controls the electronic volume, respectively, and realizes different volume functions by the respective setting data. Electronic volume device. 2. An apparatus according to claim 1, further comprising an adder for adding different setting data, a decoder for processing an addition result by said adder, and an output of said volume control circuit being set according to an output of said decoder. 2. The electronic volume device according to claim 1, wherein a volume function is realized. 3. An electronic volume, a setting data for realizing a function as a master volume, and a setting data for realizing a function as a trimmer whose adjustment range is relatively narrower than the master volume are input to control the electronic volume. An electronic volume device, comprising: a common volume control circuit that performs a function as a master volume and a function as a trimmer based on respective setting data.